1. Field of the Invention
The present invention relates to nautical lines, and more particularly to an improved safety mooring line for securing a ship.
2. Description of the Prior Art
The marine community has replaced natural fiber mooring line such as manila rope with synthetic lines such as nylon, polyester and polyproplene. The synthetic lines have the major advantages of higher strength and greater rot resistance. However the higher elasticity together with poorer rendering properties on capstans and bitts create major hazards to personnel if the line jersk or parts. When the line parts, the ends snapback at the velocity of a bullet. In the U.S. Navy alone this has resulted in 380 mishaps, of which 278 resulted in major injuries with nine fatalities, reported for the period from 1970 through May 1982. Efforts have been attempted to make the use of synthetic lines safer, such as personnel training and attention to operating procedures, early rope retirement, attention to fittings, etc. Despite approximately 30 years of usage and accidents occurring on a global scale, no synthetic mooring line is available which is restrained from snapping back from its breaking point.
The most recent attempt to solve the snapback problem is described in co-pending patent application Ser. No. 244,463 filed on Mar. 16, 1981, by Richard C. Swenson entitled "A Safety Mooring Line". Here an inner, high stretch core serves as a safety line for a high strength, low stretch synthetic fiber line so that when the line breaks, the released ends are restrained by the still intact inner core. However for larger diameter, long lines sufficient heat is generated upon the release of energy when the line parts that the inner core melts, and additionally the core is lacerated by the flailing ends of the parted line resulting in inner core failure and total line snap back. Therefore, an improved safety line is desired which does not damage the inner core upon parting.